So how do you use a gift card?
in The Commons
If I click on gift cards, it brings up a screen where it wants me to enter the gift card code. I look at the email that I got, and I see an order number and a sku number. And that's it. Are you suppose to enter one of those numbers?
Thanks.

Comments
Did you buy the giftcard for yourself? If so, then did you enter your email address correctly in the recipient box? If you did, then as well as the order acknowledgment (which just shows the SKU and sender and recipient names) you should have another email titled: "Subject: You've been sent a gift from [your name]"
In that email it should look like this:
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Gift Card
Dear ???,
[your name] [your email address] has sent you a gift card for use at DAZ 3D and it is now ready to be used for purchases.
Gift Card code - xxxxx-xxxx-xxxx-xxxx
The card has a balance of $??.?? that can be used at http://www.daz3d.com/.
Click on the code above to redeem as in-store credit.
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It's the gift card code (that string of letters and numbers with dashes inbetween) that you need to enter.
If you didn't get that email, try checking if it went to a spam filter if you have one.
Edit: Forget that if you got to see it. Applies to orders you paid for with a GC.
Yes. I bought it for myself. And yes, I got the second email you described. I never opened that one because, I knew I had bought myself a gift card. Guess I should have.
Thanks.
Also note that when you claim it, at least under certain circumstances nothing appears to happen (although it really did work), and if you try again it will appear to be failing (because you already used it). However if you check your credit, you'll see that it really did apply.